Process chambers utilized in substrate processing typically comprise a number of internal components that are repeatedly heated and cooled during and after processes are performed. In some instances, for example, when routine service or maintenance is needed after a process has been performed in a process chamber, the components are cooled to about room temperature.
In temperature controlled components, for example, such as process chamber showerheads having coolants channels, to cool the component from a typical operating temperature (e.g. about 90 degrees Celsius), a heat source that heats the component may be shut off and a coolant is flowed through the coolant channels to extract heat from the component. However, the inventors have observed when the component is cooled too rapidly, the component may incur damage. For example, when cooling a two piece showerhead having multiple parts (e.g. a body and faceplate) with different coefficients of thermal expansion coupled together via a bonding material, rapid cooling of the showerhead may unduly strain or stress the bonding material, causing the parts of the showerhead to de-bond.
To prevent such damage due to the rapid cooling, the coolant flow may be stopped or the coolant temperature may be manually increased in sequential steps to allow the component to cool slowly. However, cooling in such a manner is labor intensive and/or slow, leading to increased downtime of processing equipment and decreased efficiency of processing systems.
Accordingly, the inventor has provided improved methods of cooling process chamber components.